ABSTRACT
The laryngeal dystonias are a subset of laryngeal motor control disorders affecting voice and/or breathing, including adductor and abductor spasmodic dysphonia (SD), voice tremor, and adductor breathing dystonia. A significant proportion, about one-third, of persons with SD also have voice tremor. Diagnosis is symptom based and dependent upon excluding other laryngeal disorders such as those secondary to neurologic diseases/ disorders and those laryngeal dysfunction disorders thought to be behavioral in origin (Table 11.1). The laryngeal dystonias are relatively rare, affecting 1 in 100 000 persons.1
